This invention relates to ink-jet printing, and more particularly to filling techniques for ink-jet pens and to case structures for such pens.
Ink-jet printers are in widespread use today for printing functions in personal computers, graphics plotters, facsimile machines and other applications. Such printers typically include replaceable or semipermanent print cartridges which hold a supply of ink and carry the ink-jet printhead. The cartridge typically is secured into a printer carriage which supports one or a plurality of cartridges above the print medium, and traverses the medium in a direction transverse to the direction of medium travel through the printer. Electrical connections are made to the printhead by flexible wiring circuits attached to the outside of the cartridge. The carriage receptacle has a corresponding electrical circuit with exposed contact pads which contact cartridge interconnect pads when the cartridge is mounted in the carriage. Each printhead includes a number of tiny nozzles defined in a substrate and nozzle plate structure which are selectively fired by electrical signals applied to the interconnect pads to eject droplets of ink in a controlled fashion onto the print medium. The cartridge may be connectable to auxiliary supplies of ink for replenishing the internal supply held in the cartridge.
In order to achieve accurate printing quality, each removable cartridge includes datum surfaces which engage against corresponding carriage surfaces to precisely locate the cartridge when inserted into the carriage. In this manner, when a cartridge ink supply is exhausted, the cartridge may be replaced with a fresh cartridge, and the printhead of the new cartridge will be precisely located relative to the carriage. The printer carriage receptacle and the cartridge are therefore designed together, so that the cartridge fits accurately within the carriage receptacle, the respective circuit pads and datum surfaces match up, and the cartridge can be removed and replaced with a fresh cartridge as needed.
In accordance with an aspect of the invention, an ink filling kit is described for dispensing ink into an inkjet cartridge having a printhead nozzle array in fluid communication with at least one internal ink reservoir. The kit includes an ink supply including at least one ink chamber for holding a fill supply of liquid ink, and at least one protruding needle in communication with the at least one ink chamber. The kit can include a vacuum system for applying a vacuum to the nozzle array of the printhead nozzle array during the fill procedure to draw air through the nozzle array. A fixture system can also be provided to hold the inkjet cartridge in position during a fill procedure.
In accordance with a further aspect of the invention, a method is described for filling an inkjet cartridge having a printhead nozzle array in fluid communication with at least one internal ink reservoir. The method includes:
providing an ink supply including at least one ink chamber for holding a fill supply of liquid ink, and at least one protruding needle in communication with the at least one ink chamber;
holding the inkjet cartridge in a fixtured position during a fill procedure relative to the ink supply, wherein the at least one protruding needle extends into the at least one internal ink reservoir of the cartridge;
dispensing ink from the ink supply through the at least one needle into the at least one ink reservoir; and
applying a vacuum to the nozzle array of the printhead nozzle array during the fill procedure to draw air through the nozzle array.
In accordance with another aspect of the invention, an inkjet cartridge usable with the fill kit includes a cartridge housing having an open region, a printhead mounted on the housing, at least one internal ink reservoir defined within the housing in fluid communication with the printhead, and a foam structure disposed within the at least one internal ink reservoir. A two part lid structure is provided for covering the open region of the housing, the lid structure including a lid portion for permanent attachment to the housing, and a cover portion having a closed position for covering at least one fill port in the lid structure, the cover portion movable to allow access to the at least one fill port.